?? ?? ?????(OOP)? ??? ??? ?? ?? ??? ???? ?? ???? ???? ??? ?? ????? ?? ??? ?????. ? ?? ??? ???? ???? ?? ?? ???? ?? ??? ???? ?????.

? "?? ?? ???" ????

'?? ?? ???' ??? ???? ???? ???? ???? ?? ???? ??? ??? ???? ?? ?????. ?? ?? ??? ??? ??? ????? ?????.

?? ??? ??? ?? ??? ???? ????? ?? ??? ?? ??? ????? ?? ?????. ? ??? ??? ????? ???? ????? ??? ???? ?? ???? ??????.

????? ?: ?? ? ????

?? ?? ? ?? ???? ??? ? ????? ??? ??? ????? ???????.

"??" ?? ??

<code>class AskMonitor {
  private int value;
  private int limit;
  private String name;
  private Alarm alarm;

  public AskMonitor(String name, int limit, Alarm alarm) {
    this.name = name;
    this.limit = limit;
    this.alarm = alarm;
  }

  public int getValue() { return value; }
  public void setValue(int value) { this.value = value; }
  public int getLimit() { return limit; }
  public String getName() { return name; }
  public Alarm getAlarm() { return alarm; }
}</code>

???:

<code>AskMonitor monitor = new AskMonitor("Temperature Sensor", 100, alarm);
monitor.setValue(120);

if (monitor.getValue() > monitor.getLimit()) {
  monitor.getAlarm().warn(monitor.getName() + " is too high");
}</code>

"???" ?? ??

"Tell, Don't Ask"? ???? ?? ??? Monitor ???? ?????.

<code>class TellMonitor {
  private int value;
  private int limit;
  private String name;
  private Alarm alarm;

  public TellMonitor(String name, int limit, Alarm alarm) {
    this.name = name;
    this.limit = limit;
    this.alarm = alarm;
  }

  public void setValue(int value) {
    this.value = value;
    if (this.value > this.limit) {
      alarm.warn(name + " is too high");
    }
  }
}</code>

???:

<code>TellMonitor monitor = new TellMonitor("Temperature Sensor", 100, alarm);
monitor.setValue(120);</code>

"Tell" ??? setValue ??? ?? ??? ????? ?? ????? ?????.

? '?? ?? ???'? ??

? ??? ???: ???? ??? ???? ?????.
? Concise Code: ??? ????? ?? ??? ??????.
? ????? ??: ?? ?? ? ??? ? ??????.

? "?"?? ? ?

? ???? ??: ??? ????? ??? ?? ??? ?? ?? ??.

?: ??? ???? Monitor ??? ?? ??? ???? ???? ??? ???? ???.

? ?? ??? ??: ??? ???? ?? ??(?: ??, ??)? ?????.

?: UserProfile ??? ??? ?? ? ?? ??? ???? ???????.

? "??"?? ? ?

? ??? ??: ??? ??? ???? ?? ???? ??? ??

?: User ??? ??? ??? ?????.

? ?? ????: ??? ?? ??? ???? ??.

?: ???? ??? ???? ???? ?? Person? ??? ????.

? ?? ??: ??? ???? ?? ??? ?? ?? ??? ???? ??? ??.

?: Router? ??? ??? ?? Server? ??? ?????.

? ????

??? ?????? ? ????? ?? ???? ?? ???? ?????!

• 100??? ???? KISS ??? ??
• 100??? ???? DRY ??

?? ???? ?? ?? ??? ?????:

• ????
• ???
• ???/X

? ??? '??? ?? ???' ??? ? ? ?? ??? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!